Believe in "E.T."?

[done]

I had always thought that there must be HUGE numbers of planets out there that support life.

In the last 20 years however, we have discovered many more "special" things needed for life to reach our level.

1. Need to be in the habitable zone (high number of planets meet this requirement).

2. Need to have chemical components for life present (high number of planets meet this requirement)

3. Need to have dual liquid/solid core capable of generating strong planetary magnetic field (our is believed to have come from being hit by a Mars sized planet)

4. Need to have a low number of comets and large asteroids (too many collisions and advanced life cannot evolve). The orbital shifts of Jupiter and Saturn cleared the larger asteroid and many comets out of the solar system to help us enter the calm period we are in now for impacts)

5 - ?

There just seems to be more and more items stacked up that had to come together for us to be here. I mean look at Venus, roughly earth sized, and has  a runaway green house effect and crushing acidic atmosphere.

Of course, as far as we know we have an infinite universe which goes to say, within an infinite universe everything is likely to happen over and over again.

I would not think we would be that extraordinary but all the recent scientific discoveries seem to make us sound more and more unique.

With Kepler out there and the next generation of space telescopes going out in the next 20 years, we shall see,

[South FLA]

Most likely life on other planets exist.

No, I don't believe any advanced life forms have visited earth or even come close (Prime Directive).

Nevertheless, if E.T. could wisk me away to a planet full of trophy game fish along with my boat and all my tackle I'd be in heaven. I'd ask him to bring me back though so I could post the pics of my fishing trip on the forum ;D.

To each his own.

[FishingBuds]

I see Green People  

[joshuaryan]

There is so much much out there that we haven't explored that we'd be foolish to think we're the one ones.  I believe.

[bigmountaineer]

No I believe in earth and that's the extent of intelligent life.

[CGH]

Not only do I believe but I sleep with one every night  

[Tokyo Tony]

No I believe in earth and that's the extent of intelligent life.

Any reason?

[done]

No I believe in earth and that's the extent of intelligent life.

Although, I have had days at work where I am not so sure intelligent life exists even here. LOL.

[MaineBassMan]

I believe, that's why I wear a steel chastity belt that is extra thick on the back side, If you know what I mean , whenever I'm out hunting or fishing!!

[Hawghead]

I'll keep my ideas focused on scientific ideas and won't dabble into faith/religion.

Looking for evidence of intelligent life elsewhere is a very low percentage task. SETI is the acronym for the organization that is the leader in the search for 'E.T.' The can break it into a mathematical equation. Basically looking at and estimating the odds of several factor being favorable for life to exist AND make contact. It's called the Drake equation.

As many have already indicated the conditions needed for life to exist are very very specific. If the Earth's properties (meaning distance from sun, size of planet, size of sun, etc) changed hardly at all or where different from the get go Earth would be inhospitable to humans. So the conditions we have on earth are very very specific and rare.

Second, intelligent life. How likely is it that IF life COULD exist, that it actually did again spontaneously start as it did on earth. So lets say it did what are the odds that intelligent life developed and that they have technology capable of contacting other planets, or could detect evidence of life on other planets, or are even looking, or have technology that we could even detect?

Third, time. As others have stated. The distance issue is huge. Other civilizations could have developed sent out radio signals that we theoretically could detect. But they made be 10 billion light years away. Well all electromagnetic radiation travels at the speed of light, 186,000 miles per second. So it will take 10 billion light years for there 'signal' to reach earth. It could have passed earth 500 million years ago, or not get to us for another 5 billion years.....either way we didnt or wont have the capability to detect it.

When one considers the sheer vastness of the universe it seems very hard to logically deny the possibility of life existing elsewhere, the odds of us finding it unfortunately are quite remote.

The numerical answer to the equation isn't important as the fact that it illustrates the extent to which odds are stacked against us detecting life on another planet.

[done]

   You also have to be humbled by how absolutely little we know about life in general. I mean I remember going to elementary and high school and what we taught in school as FACT. The death of the Dinosaurs was unknown, Pluto was a planet....

  All you needed for life at that point (as we knew it) was a planet in the proper orbital range and whammo, you had life.

  Since then, we have learned about the importance of a magnetic field, of relatively a low number of large comet/asteroid impacts, a stable climate, plate tectonics, etc.

  On one hand this stuff is totally cool. On the other, it is almost overwhelming.

  I will tell you guys this though. One night in Winter, 1998 about 1 am I was driving I-90 South of Buffalo, NY (near hamburg and the Buffalo AP) heading north with one of the girls from my dorm to hit the casino in Niagara falls.  I saw what I first thought was an airplane flying high altitude perpendicular to the highway. It stopped and in that instant split into 3 separate lights, one went back on the same path it came in on, one kept going forward, one went straight up. I saw it, and the girl I was traveling saw it (though it took us 20 minutes to admit it cause we both thought we were crazy). I have spent a lot of time trying to rectify what man made or natural phenomenon could have caused what I saw. I have not yet been able to explain it.

    Stuff like that is what keeps me wondering on have we ever been visited. Rationally, i could see aliens visiting earth for anthropology studies, or something like that, maybe scoping out a potential new home world for themselves (since life supporting planets appear so rare). Not sure what other reasonable explanations would be. For all we know though, there could be minerals on our planet that may be rare in the universe. Who knows. I doubt it would be ot seek our knowledge or anything hokey like that.